Aldehyde and glycosidase-treated soft and bone tissue xenografts

• US 6,231,608 B1
• Filed: 02/11/1999
• Issued: 05/15/2001
• Est. Priority Date: 06/07/1995
• Status: Expired due to Term

• Current Assignee: Aperion Biologics, Inc.
• Original Assignee: CROSSMARK Incorporated
• Inventors: Stone, Kevin R.
• Primary Examiner(s): Isabella, David J.
• Application Number:
  US09/248,476
• Time in Patent Office: 824 Days
• Field of Search: 623/11.11, 623/13.11, 623/13.17, 623/16.11, 623/23.6, 623/23.61, 623/23.64, 623/23.72, 623/23.75, 623/23.76, 424/423, 424/422, 424/548, 424/549, 435/1.1, 435/1.3, 600/36
• US Class Current: 623/16.11
• CPC Class Codes: A61F 2/08 Muscles; Tendons; Ligaments sutures A61B17/04
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/30756 Cartilage endoprostheses A61F2/3603 takes precedence
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2/38 for elbows or knees
• CPC Class Codes: A61F 2/3872 Meniscus for implantation between the natural bone surfaces
• CPC Class Codes: A61F 2002/2817 Bone stimulation by chemical reactions or by osteogenic or biological products for enhancing ossification, e.g. by bone morphogenetic or morphogenic proteins [BMP] or by transforming growth factors [TGF]
• CPC Class Codes: A61F 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/30677 Means for introducing or releasing pharmaceutical products, e.g. antibiotics, into the body
• CPC Class Codes: A61L 2/0035 Gamma radiation
• CPC Class Codes: A61L 2/10 Ultraviolet radiation
• CPC Class Codes: A61L 2430/40 Preparation and treatment of biological tissue for implantation, e.g. decellularisation, cross-linking
• CPC Class Codes: A61L 27/3604 characterised by the human or animal origin of the biological material, e.g. hair, fascia, fish scales, silk, shellac, pericardium, pleura, renal tissue, amniotic membrane, parenchymal tissue, fetal tissue, muscle tissue, fat tissue, enamel
• CPC Class Codes: A61L 27/3608 Bone, e.g. demineralised bone matrix [DBM], bone powder
• CPC Class Codes: A61L 27/3625 Vascular tissue, e.g. heart valves
• CPC Class Codes: A61L 27/3645 Connective tissue
• CPC Class Codes: A61L 27/365 Bones
• CPC Class Codes: A61L 27/3687 characterised by the use of chemical agents in the treatment, e.g. specific enzymes, detergents, capping agents, crosslinkers, anticalcification agents
• CPC Class Codes: A61L 27/3691 characterised by physical conditions of the treatment, e.g. applying a compressive force to the composition, pressure cycles, ultrasonic/sonication or microwave treatment, lyophilisation

Abstract

The invention provides articles of manufacture comprising substantially non-immunogenic soft and bone tissue xenografts for implantation into humans. The invention further provides methods for preparing soft and bone tissue xenografts by removing at least a portion of a soft or bone tissue from a non-human animal to provide a xenograft; washing the xenograft in saline and alcohol; subjecting the xenograft to cellular disruption treatment; exposing the xenograft to an aldehyde in an amount ranging from about 0.01% to about 0.10%; and digesting the xenograft with a glycosidase and optionally following with a capping treatment. The invention also provides an article of manufacture produced by the above-identified method of the invention. The invention further provides a soft or bone tissue xenograft for implantation into a human including a portion of a soft or bone tissue from a non-human animal, wherein the portion has extracellular components and substantially only dead cells. The extracellular components have substantially no surface carbohydrate moieties which are susceptible to glycosidase digestion. The extracellular components also have an aldehyde in an amount ranging from about 0.01% to about 0.10% crosslinking the proteins of the extracellular components. Each of the xenografts of the invention are substantially non-immunogenic and have substantially the same mechanical properties as a corresponding native soft or bone tissue.

Claims

1. A method of preparing a xenograft formed of a soft or bone tissue for implantation into a human, which comprises

a. removing at least a portion of the soft or bone tissue from a non-human animal to provide a xenograft;

b. washing the xenograft in water and alcohol;

c. subjecting the xenograft to a cellular disruption treatment;

d. exposing the xenograft to an aldehyde in an amount ranging from about 0.01% to about 0.10%; and

e. digesting the xenograft with a glycosidase to remove substantially a plurality of first surface carbohydrate moieties from the xenograft whereby the xenograft is substantially non-immunogenic and has substantially the same mechanical properties as the native soft or bone tissue.

2. A method according to claim 1, wherein the step of exposing the xenograft to an aldehyde comprises exposing the aldehyde to an aldehyde selected from the group consisting of glutaraldehyde, formaldehyde, and adipic dialdehyde.

3. A method according to claim 1 further comprising the step of

after step c, piercing the xenograft.

4. A method according to claim 1 further comprising the step of

after step c, treating the xenograft with a second enzyme.

5. A method according to claim 4, wherein the second enzyme is selected from the group consisting of ficin and trypsin.

6. A method according to claim 1 further comprising the step of

after step c, treating the xenograft with one or more agents selected from the group consisting of anticalcification agents, antithrombotic agents, antibiotics, and growth factors.

7. A method according to claim 1 further comprising the step of

after step c, sterilizing the xenograft.

8. A method according to claim 7, wherein the sterilizing step comprises sterilizing the xenograft with one or more agents selected from the group consisting of ethylene oxide and propylene oxide.

9. A method according to claim 1 further comprising the step of:

after step c, treating the xenograft with polyethylene glycol.

10. A method according to claim 1 further comprising the step of

after step c, exposing the xenograft to one or more agents selected from the group consisting of aliphatic diamine compounds and aromatic diamine compounds.

11. A method according to claim 1, wherein the cellular disruption treatment comprises freeze/thaw cycling.

12. A method according to claim 1, wherein the cellular disruption treatment comprises exposure to gamma radiation.

13. A method according to claim 1, wherein the glycosidase is a galactosidase.

14. A method according to claim 13, wherein the galactosidase is an α

-galactosidase.

15. A method according to claim 1 further comprising the step of

after step e, treating a plurality of second surface carbohydrate moieties on the xenograft with a plurality of capping molecules to cap at least a portion of the second surface carbohydrate moieties.

16. A method according to claim 15, wherein at least a portion of the capping molecules are a plurality of fucosyl molecules.

17. A method according to claim 15, wherein at least a portion of the capping molecules are a plurality of n-acetyl glucosamine molecules.

18. A method according to claim 1 further comprising the step of

after step d, removing substantially a plurality of proteoglycans from the xenograft, wherein the xenograft is a soft tissue.

19. A method according to claim 18, wherein the removing step comprises digesting the xenograft with one or more proteoglycan-depleting factors selected from the group consisting of chondroitinase ABC, hyaluronidase, chondroitin AC II lyase, keratanase, trypsin and fibronectin fragments.

20. A method according to claim 1, wherein the removing step comprises removing the portion of a medial or lateral meniscus having a superior principal surface and an inferior principal surface, each of the principal surfaces having an outer portion being joined by an outer lateral surface, and each of the principal surfaces having an inner portion being joined by an inner lateral surface.

21. A method according to claim 1, wherein the removing step comprises removing the portion of a ligament.

22. A method according to claim 21, wherein the removing step comprises removing with the portion a first block of bone attached to a first end of the portion.

23. A method according to claim 22, wherein the removing step comprises removing with the portion a second block of bone affixed to a second end of the portion opposite the first end.

24. A method according to claim 1, wherein the removing step comprises removing the portion of an articular cartilage.

25. A method according to claim 24, wherein the removing step comprises removing with the portion a layer of subchondral bone.

58. A method according to claim 1, wherein the step of exposing the xenograft to an aldehyde comprises exposing the xenograft to the aldehyde in an amount ranging from about 0.01% to about 0.05%.

26. An article of manufacture comprising a substantially non-immunogenic aldehyde-treated, glycosidase-treated xenograft formed of a soft or bone tissue for implantation into a human, produced by the process of

a. removing at least a portion of the soft tissue, hard tissue or heart valve from a non-human animal to provide a xenograft;

b. washing the xenograft in water and alcohol;

c. subjecting the xenograft to a cellular disruption treatment;

d. exposing the xenograft to an aldehyde in an amount ranging from about 0.01% to about 0.10%; and

e. digesting the xenograft with a glycosidase to remove substantially a plurality of first surface carbohydrate moieties from the xenograft whereby the xenograft is substantially non-immunogenic and has substantially the same mechanical properties as the native soft or bone tissue.

27. An article of manufacture according to claim 26, wherein the aldehyde is selected from the group consisting of glutaraldehyde, formaldehyde, and adipic dialdehyde.

28. An article of manufacture according to claim 26, wherein the xenograft has a plurality of punctures for increasing permeability to agents and enzymes.

29. An article of manufacture according to claim 26 further comprising one or more agents selected from the group consisting of anticalcification agents, antithrombotic agents, antibiotics, and growth factors.

30. An article of manufacture according to claim 26, wherein the xenograft is sterilized.

31. An article of manufacture according to claim 26, wherein the xenograft is a polyethylene glycol-treated xenograft.

32. An article of manufacture according to claim 26, further comprising an agent selected from the group consisting of aliphatic diamine compounds and aromatic diamine compounds.

33. An article of manufacture according to claim 26, wherein the glycosidase-treated xenograft is a galactosidase-treated xenograft.

34. An article of manufacture according to claim 33, wherein the galactosidase-treated xenograft is an α

-galactosidase-treated xenograft.

35. An article of manufacture according to claim 26 further comprising a plurality of capping molecules capped on a plurality of second surface carbohydrate moieties on the xenograft.

36. An article of manufacture according to claim 35, wherein the capping molecules comprise a plurality of fucosyl molecules.

37. An article of manufacture according to claim 35, wherein the capping molecules comprise a plurality of n-acetyl glucosamine molecules.

38. An article of manufacture according to claim 26, wherein the xenograft is a thawed, frozen xenograft.

39. An article of manufacture according to claim 26, wherein the xenograft is a gamma-irradiated xenograft.

40. An article of manufacture according to claim 26, wherein the xenograft is a proteoglycan-depleting factor-treated xenograft, and wherein one or more of the proteoglycan-depleting factors is selected from the group consisting of chondroitinase ABC, hyaluronidase, chondroitin AC II lyase, keratanase, trypsin, and fibronectin fragments.

41. An article of manufacture according to claim 26, wherein the portion is of a medial or lateral meniscus having a superior principal surface and an inferior principal surface, each of the principal surfaces having an outer portion being joined by an outer lateral surface, and each of the principal surfaces having an inner portion being joined by an inner lateral surface.

42. An article of manufacture according to claim 26, wherein the portion is of a ligament.

43. An article of manufacture according to claim 42, wherein the portion of the ligament comprises a first block of bone attached to a first end of the portion.

44. An article of manufacture according to claim 43, wherein the portion of the ligament comprises a second block of bone affixed to a second end of the portion opposite the first end.

45. An article of manufacture according to claim 26, wherein the portion is of an articular cartilage.

46. An article of manufacture according to claim 45, wherein the portion of the articular cartilage comprises a layer of subchondral bone.

59. An article of manufacture according to claim 26, wherein the xenograft is produced by exposing the xenograft to the aldehyde in an amount ranging from about 0.01% to about 0.05%.

47. A xenograft formed of a soft or bone tissue for implantation into a human, comprising:

a portion of the soft or bone tissue from a nonhuman animal, wherein the portion includes a plurality of extracellular components, a plurality of substantially only dead cells, and a plurality of proteins within said extracellular components,

said protein s crosslinked with an aldehyde in an amount ranging from about 0.01% to about 0.10%, the extracellular components and the dead cells having substantially no surface carbohydrate moieties which are susceptible to glycosidase digestion, and

whereby the portion is substantially non-immunogenic and has substantially the same mechanical properties as a corresponding portion of the native soft or bone tissue.

48. A xenograft according to claim 47, wherein the aldehyde is in an amount ranging from about 0.01% to about 0.05% crosslinking the proteins.

49. A xenograft according to claim 47, wherein the portion has capping molecules linked to at least a portion of a plurality of surface carbohydrate moieties on the xenograft, and whereby the xenograft is substantially non-immunogenic.

50. A xenograft according to claim 49, wherein at least a portion of the capping molecules are a plurality of fucosyl molecules.

51. A xenograft according to claim 49, wherein at least a portion of the capping molecules are a plurality of n-acetyl glucosamine molecules.

52. A xenograft according to claim 47, wherein the portion is of a medial or lateral meniscus having a superior principal surface and an inferior principal surface, each of the principal surfaces having an outer portion being joined by an outer lateral surface, and each of the principal surfaces having an inner portion being joined by an inner lateral surface.

53. A xenograft according to claim 47, wherein the portion is of a ligament.

54. A xenograft according to claim 53, wherein the portion of the ligament comprises a first block of bone attached to a first end of the portion.

55. A xenograft according to claim 54, wherein the portion of the ligament comprises a second block of bone affixed to a second end of the portion opposite the first end.

56. A xenograft according to claim 47, wherein the portion is of an articular cartilage.

57. A xenograft according to claim 56, wherein the portion of the articular cartilage comprises a layer of subchondral bone.